Dirk Bergmann

Folder org already exists/Too many open files with Netbeans

The messages "Folder org already exists in ..." and "Too many open files" when using Netbeans are likely related. The underlying error might be that Linux runs out of file descriptors, which can happen rather quickly when you open many projects at once. Here's the solution.

The file descriptors can be set at the system level and at the shell level:

Check how many your system allows:

cat /proc/sys/fs/file-max

This value can be set to a high number, probably to several 100k without major issues. For now you might try:

echo "65536" >/proc/sys/fs/file-max

You could also add

fs.file-max = 65536

to

/etc/sysctl.conf

then run

sysctl -p

to reload sysctl.conf

For the shell type

ulimit -n

to get the number of file descriptors.

You can set for example

soft nofile 8192

hard nofile 8192

in

/etc/security/limits.conf

to increase the number.

After increasing these values I have not had any issues with Netbeans as described above for several months now. Hope it helps.